KRONFELD ON GLIDING AND SOARING.pdf - Lakes Gliding Club

266 KRONFELD ON GLIDING & SOARING
two-seaters which have proved their worth. The constructive
problems to which they give rise are caused by the
difficulty of providing such large machines with flyingcontrols
which are in any way similar to the normal machines
of the same type. And a two-seater soarer must be a large
machine, if only to obtain the flying qualities necessary for
carrying the double load. A very good solution of the
problem is supplied by a glider, in the construction of which
steel tubing plays an important part. The school twoseater,
designed by Krekel, " Mecklenburg M III," is a
braced monoplane which has been developed chiefly with an
eye to good flying qualities. The wings are constructed in
four parts, the inner being square ended. The outer
sections are attached at the bracing points and have a
triangular plan form with rounded tips. In the inner
section the two spars have diagonal, wooden strut dragbracing
between them and in the outer section the two spars
come together at the tips. The ailerons are large and
extend the whole length of the outer wings. With the
exception of the wing all parts are built of steel tubing. The
cockpit in which the pilot and passenger sit is covered with
doped fabric. This glider has excellent flying qualities,
either as a single-seater or a two-seater, in the former
case its strong point is that it has an extraordinary low
sinking speed, and may be used as required for a variety
of purposes.
The " Mecklenburg M III " was evolved from the
light-wind type, but the " Hercules," two-seater, designed
by Arnold, is a clever development of the " Priifling " type.
It has a two-piece wing, which is braced to the fuselage by
two parallel struts. On the fuselage itself the central
section is not secured at four points but by means of two
supports projecting from the framework. The elevators,
unlike those of the " Priifling," are not on the fuselage but
are located on the fin, where the lofty position shields them
from injury on landing and has proved a most useful means
of holding this glider while being launched.
Although the two-seater has hitherto played no great role
in training work, it has been most useful as a means of
propaganda. It affords a skilled pilot an opportunity of